The present invention relates to an ordering device for arranging products received in a loose state in an orderly succession.
The present invention is advantageously applied in the manufacture of an ordering device for feeding products in general, and sweets or chocolates in particular, to a wrapping machine, to which the description below makes specific reference, although without limiting the scope of application of the invention.
Ordering devices of the above-mentioned type are normally installed between a wrapping machine, designed to receive the products to be wrapped in an orderly succession, that is to say, at a constant distance from one another, and a feed device of the type described, for example, in U.S. Pat. No. 4,469,219, designed to feed aligned, orderly products in succession, at a precise regular distance from one another.
European Patent No. 485,845 describes known ordering devices designed to feed an orderly succession of products received in the loose state to an operating machine, of the type comprising first and second conveyors with belts which are closed in a loop around respective transmission pulleys and positioned side-by-side to define a product feed path with preset total length, and comprising first and second active portions with variable lengths, equal to complementary fractions of the total length. The transmission pulleys connected to the two conveyor belts define the first and second active portions, supported by a carriage which moves in both directions parallel with said path. There are also drive means which drive the carriage to move the transmission pulleys so as to vary the length of the first and second portions, and means for compensating the variations in the length of the active portions of the path with corresponding opposite variations in the length of complementary sections, respectively active and passive, of the belts.
In the known devices of the type described above, the compensator means are integrated in the drive means and normally comprise a looped belt, which is divided into two portions with substantially equal length by two carriages, which slide on respective guides parallel with the first and second portions and support the belt transmission pulleys.
The upper carriage is positioned in the zone at which the two belts are separated, to which the products are transferred in succession, whilst the lower carriage, translating inside the device structure in the direction opposite to that of the upper carriage, compensates the variations in the length of the active sections of the belts, and suitably tensions the belts.
In the known ordering devices in question, the presence of long belts, which run almost the entire length of the device, although useful, creates several disadvantages, especially when the products received in the loose state are quite close together and/or the device operates at high speeds.
In such conditions, the products are arranged at a precise regular distance from one another in an orderly succession with brief, rapid movements of the carriage, which is, therefore, subject to sudden acceleration and stops. As a result of the forces of inertia which subject the carriages to stress, the belts are subjected to equally sudden stresses which mean that product positioning is not perfectly regular and, if repeated a significant number of times, rapidly cause the belts to wear.
The aim of the present invention is to provide an ordering device of the above-mentioned type, which overcomes the above-mentioned disadvantages.
Accordingly, the present invention provides an ordering device for arranging products, received from a feed device, in an orderly succession to feed an operating machine. The device includes first and second conveyor means with belts which are closed in loops and aligned with one another to form a product feed path with a preset total length, said path including first and second active portions, with variable lengths equaling complementary fractions of the total length; there being transmission means connected to the belts to define said first and second active portions, supported by a carriage which moves in both directions parallel with the feed path; drive means operating on the carriage to move the transmission means and so vary the length of the first and second portions; means for compensating the variations in the length of the active portions of the path with corresponding opposite variations in the length of complementary sections, respectively active and passive, of the belts, the device comprising only one carriage, the compensator means comprising mechanisms which have rigid elements that are joined to one another to form a linkage connecting the carriage and the belts in such a way as to vary the geometric configuration of the belts according to the movements of the carriage.